FAL Build

[nneely]

I am currently building a FAL and I'm having some issues. Specifically I am using a South African barrel and trying to mate it with an Entreprise receiver however I cannot get the barrel to thread completely into the receiver. Now I'm told that a common step with metric barrels is having them lathed to fit. Am I missing something?

 

[Frankl03]

Go to the FAL files. You should be able to get all your questions answered there!

Hope that helps!

 

[nneely]

Go to the FAL files. You should be able to get all your questions answered there!

Hope that helps!

I posted there as well, I figured the more places I post the more info available.

 

[BBBBill]

The metric barrels were supposed to have been "timed" during manufacture to allow them to turn up to about 10-11 oclock for final torque to 12 oclock. The process was much more controlled with fixturing and gaging at time of manufacture. Inch pattern guns took a little different approach, using various thickness "breaching washers" to adjust the fit of barrel to receiver. On the metric kits that I built using DSArms and Imbel receivers, all but one (10 STG 58 kits and 5 others) turned up to 10-11 oclock upon initial fit. That was after checking/cleaning the barrel threads to ensure no damage, etc. On the one that didn't, I made a breaching washer from thin stainless shim stock which solved the problem. I've never used an Entreprise receiver, but anecdotal evidence says that you might need to do some adjustment to the barrel shoulder or the receiver face. That is lathe and mill work and should be done only after carefully gaging both. I would suspect that the receiver face have a bit of extra material. Carefully analyse everything before cutting as any change you make may have multiple secondary effects. The FAL Files used to be a great resource, but I haven't been over there in a long time, so I don't know how it may have evolved after some of the "food fights" that erupted.

 

[nneely]

The metric barrels were supposed to have been "timed" during manufacture to allow them to turn up to about 10-11 oclock for final torque to 12 oclock. The process was much more controlled with fixturing and gaging at time of manufacture. Inch pattern guns took a little different approach, using various thickness "breaching washers" to adjust the fit of barrel to receiver. On the metric kits that I built using DSArms and Imbel receivers, all but one (10 STG 58 kits and 5 others) turned up to 10-11 oclock upon initial fit. That was after checking/cleaning the barrel threads to ensure no damage, etc. On the one that didn't, I made a breaching washer from thin stainless shim stock which solved the problem. I've never used an Entreprise receiver, but anecdotal evidence says that you might need to do some adjustment to the barrel shoulder or the receiver face. That is lathe and mill work and should be done only after carefully gaging both. I would suspect that the receiver face have a bit of extra material. Carefully analyse everything before cutting as any change you make may have multiple secondary effects. The FAL Files used to be a great resource, but I haven't been over there in a long time, so I don't know how it may have evolved after some of the "food fights" that erupted.

Thanks for the info!

 

[HankC]

Many use a grinder sanding disc pad (30 grits?) to remove shoulder material by hand sanding. Do it slowly, does not take much. Make a center hole to pass the threaded portion, hand sand and try fitting until you can hand time to around 10.5-11 O'C. (better check it first) Go to FALFILES as suggested, there are sticky and many good postings on this matter. Folks there are very helpful, but do your search first.

 

[Clark]

I have put the washer on fine sand paper on a flat ground surface and rubbed, rotated, repeat until it fit.

I have turned material off on the lathe.

When I turned off too much on the lathe and it over clocked, I hit the side of the breech with a hammer until the barrel grew back. I got that trick from the work book
Gunplumber's guide to FN FAL Home Gunsmithing, by Arizona Response Systems
http://gunthings.com/faltools.htm

That was over 10 years ago.

 

[nneely]

Well I lathed the barrel very small increments until it was perfect. All said and done I took off about 1/1000 of an inch and it hand tightens between 10.5 and 11 o'clock. Thanks for all the help guys.